Articles are known having numerous lengths of light-transmitting or "optical" filament, each having a short "inserted" end extending through a piece of fabric and exposed to view at the "front" or display side of the fabric; at the back of the fabric, trailing lengths of filament extend from the short inserted ends to remote ends ("trailing" ends) for exposure to light sources.
U.S. Pat. No. 4,875,144, issued Sep. 14, 1987, to Harry L. Wainwright, discloses an example of such articles. In the Wainwright patent, the trailing lengths of filament are gathered in bundles; the filaments of each bundle are illuminated concurrently by a common light source. The exposed ends of the filaments of each group form a design that is lit up; multiple patterns of filament ends are lit up concurrently and in sequence, developing a succession of display patterns.
The fabric in such articles is ordinarily a textile, but it may be of any suitable material, synthetic leather for example.
Each filament is commonly a monofilament, but a thread comprising multiple fine light-transmitting fibers may constitute what is here called "a filament".
U.S. Pat. No. 4,854,250 discloses a machine for inserting optical filaments into a fabric, for use in making articles decorated by optical filaments intended to be illuminated. There is no provision in that patent for forming bundles of filaments or otherwise organizing the filaments in groups, in order for filaments that form a pattern to be illuminated concurrently by a common light source.
Still further, an unpublicized method has been proposed for making such articles wherein a short end of an optical filament is inserted into a fabric by a hollow needle; the needle is withdrawn leaving a short inserted end of each filament projecting through the fabric to the front or display side of the fabric; those short ends are adhered to the fabric by rapidly polymerized "glue". Long trailing lengths of the filaments extend from the back of the fabric; those trailing lengths are gathered or organized in groups manually, so that all the filaments of a group can be illuminated together.